KR20240014528A - Active metal brazing paste composition, brazing paste, and method for brazing ceramics and metals - Google Patents

Abstract

An active metal solder paste composition comprising a binder and metal powder. Metal powders include active metal solder powder and flux metal powder; The flux metal powder includes copper powder and/or copper-silver alloy powder; Active metal solder powder is an alloy powder of copper, silver and active metal; Based on the total weight of the metal powder, the content of active metal is greater than 1.5 wt%, the content of silver is 40-90 wt%, and the content of oxygen is less than 0.5 wt%. The composition can stabilize soldering quality and reduce material costs. This application also relates to solder pastes and methods for soldering ceramics and metals.

Description

Active metal solder paste compositions, solder pastes, and methods for soldering ceramics and metals

Cross-reference to related applications

This disclosure was filed with the State Intellectual Property Office of China on September 29, 2021 and is entitled “ACTIVE METAL BRAZING PASTE COMPOSITION, BRAZING PASTE, AND METHOD FOR BRAZING CERAMICS AND METAL” Priority is claimed on Chinese Patent Application No. 202111155220.8, "BRAZING PASTE, AND METHOD FOR BRAZING CERAMICS AND METALS". The entire contents of the above-referenced patent disclosure are incorporated herein by reference.

Field

This disclosure relates to the field of brazing technology, and more particularly to active metal brazing paste compositions, brazing pastes, and methods for brazing ceramics and metals.

Currently, active metal brazing is a common method for brazing ceramics to ceramics and metals to ceramics, especially non-oxide ceramics such as silicon nitride and aluminum nitride. During active metal brazing, a brazing material containing active metals such as Ti or Zr is used. These active metals can react with ceramics at high temperatures, increasing the wettability of the brazing material and forming chemical bonds with the ceramics. A common brazing method is to add a binder to powdered brazing material and then screen print it on the brazing interface. The binder is formed by mixing different types of organic materials. Before the brazing temperature is reached, most of the binder evaporates and leaves the brazing interface. However, some organic materials decompose, resulting in carbon residues at the brazing interface, which can affect brazing quality and subsequent processes. In existing ternary alloy active metal brazing materials, the content of active metals is low, and it is difficult to precisely control the content of active metals in ternary alloy products during formulation, which leads to significant fluctuations in the content of active metals. The content of active metals has a significant effect on brazing, so variations will cause instability in subsequent brazing quality. Additionally, existing active metal brazing materials have high silver content, which causes an increase in the cost of the brazing materials.

The purpose of the present disclosure is to solve the problem of carbon remaining at the brazing interface, affecting the brazing quality and subsequent processes, the difficulty in precisely controlling the content of active metals in the brazing material, and the high costs. .

To achieve the above object, in a first aspect, the present disclosure provides an active metal brazing paste composition. The composition includes a binder and metal powder. Metal powders include active metal brazing powders and brazing-aid metal powders. The brazing-auxiliary metal powder contains copper powder and/or copper-silver alloy powder. Active metal brazing powder is an alloy powder containing copper, silver and active metal. Based on the total weight of the metal powder, the active metal content is 1.5 wt% or more, the silver content is 40 wt% to 90 wt%, and the oxygen content is 0.5 wt% or less.

In some examples of the disclosure, based on the total weight of the brazing-auxiliary metal powder, the oxygen content of the brazing-auxiliary metal powder is 2 wt% or less, and the carbon content of the brazing-auxiliary metal powder is 0.75 wt% or less. , the molar ratio of oxygen to carbon in the brazing-auxiliary metal powder is 2 or more.

In some examples of the disclosure, the oxygen content of the brazing-assisting metal powder is 0.3 wt% to 0.5 wt%, and the carbon content is 0.1 wt% or less, based on the total weight of the brazing-assisting metal powder.

In some examples of the disclosure, the content of the brazing-auxiliary metal powder is 10 wt% to 50 wt% and the content of the active metal brazing powder is 50 wt% to 90 wt%, based on the total weight of the metal powder. .

In some examples of the disclosure, based on the total weight of the metal powder, the content of active metal is 1.8 wt% to 4.5 wt%, the content of silver is 42 wt% to 85 wt%, and the content of oxygen is 0.001 wt%. % to 0.3 wt%.

In some examples of the disclosure, based on the total weight of the metal powder, the content of active metal is 2 wt% to 4 wt%, the content of silver is 45 wt% to 80 wt%, and the content of oxygen is 0.06 wt%. % to 0.2 wt%.

In some examples of the disclosure, the active metal is selected from one or more of Ti, Zr, and Hf.

In some examples of this disclosure, the active metal is Ti.

In some examples of the present disclosure, the content of active metal is 1.5 wt% to 10 wt%, based on the total weight of the active metal brazing powder.

In some examples of the present disclosure, the content of active metal is 2 wt% to 6 wt%, based on the total weight of the active metal brazing powder.

In some examples of the present disclosure, the weight ratio of Ag to Cu in the active metal brazing powder is between 3:7 and 9:1.

In some examples of this disclosure, the weight ratio of Ag to Cu in the active metal brazing powder is between 6:4 and 8:2.

In some examples of the disclosure, the oxygen content of the active metal brazing powder is 0.5 wt% or less.

In some examples of the disclosure, the particle size of the active metal brazing powder is 50 μm or less and the particle size of the brazing-auxiliary metal powder is 50 μm or less.

In some examples of the disclosure, the content of metal powder is 80 wt% to 95 wt% and the content of binder is 5 wt% to 20 wt%, based on the total weight of the composition.

In some examples of the present disclosure, the content of metal powder is 85 wt% to 90 wt% and the content of binder is 10 wt% to 15 wt%, based on the total weight of the composition.

In a second aspect, the present disclosure provides a brazing paste. The brazing paste is prepared by employing the active metal brazing paste composition according to the first aspect of the present disclosure.

In a third aspect, the disclosure provides a method for brazing ceramics and metals by employing an active metal brazing paste composition according to the first aspect of the disclosure or a brazing paste according to the second aspect of the disclosure. . The method includes connecting the ceramics to be brazed and the metals to be brazed through a composition or brazing paste to form a connecting member to be brazed, and feeding the connecting member to be brazed into a vacuum brazing furnace to be heated and brazed. And, the content ratio of the organic materials of the connecting member to be brazed to the effective volume of the vacuum brazing furnace is 0.4 g/㎥ or less.

In some examples of the disclosure, the method includes printing a composition or brazing paste onto the surface of ceramics to be brazed, and baking at 60° C. to 100° C. for 20 to 60 minutes; The metals to be brazed are securely connected with the baked brazing paste to obtain a connecting member to be brazed; It further includes that the connecting member to be brazed is heated and supplied to a vacuum brazing furnace to be brazed, and the content ratio of the organic materials in the connecting member to be brazed to the effective volume of the vacuum brazing furnace is 0.3 g/㎥ or less.

Through the above technical solution, the active metal brazing paste composition according to the present disclosure includes copper powder and/or copper-silver alloy powder, due to the presence of an oxide layer on the surface of the copper powder and/or copper-silver alloy powder. , copper is easily oxidized and decomposed into oxygen at the brazing temperature, which consumes the carbon remaining after decomposition of the organic materials in the binder, which can improve the reactivity of the brazing material. The active metal brazing paste composition according to the present disclosure contains copper powder or silver-copper alloy powder in addition to the active metal brazing powder, which avoids the difficulty in directly controlling the content of the active metal in the alloy powder, Therefore, by adjusting the amount of copper powder or silver-copper alloy powder in the composition, the total content of active metal in the brazing paste can be adjusted and controlled, thereby stabilizing the brazing quality and reducing the effects on subsequent processes. . Meanwhile, copper powder and silver-copper alloy powder are inexpensive, which can reduce material cost after being added to the brazing paste composition.

The advantages of examples of the present disclosure will be explained in part in the specification below. Some of these advantages may be apparent from the specification, or may be acquired through implementation of examples of the disclosure.

The accompanying drawings are intended to provide a better understanding of the present disclosure and constitute a part of this specification. The accompanying drawings and the specific implementations below are used together to explain the disclosure rather than limit the disclosure. In the accompanying drawings:
1 is an image of ultrasonic detection at a brazed location of a brazing assembly according to Example 1.
Figure 2 is an image of ultrasonic detection at the brazed location of a brazing assembly according to Comparative Example 1.
3 is an image of ultrasonic detection at the brazed location of a brazing assembly according to Comparative Example 2.
4 is an image of ultrasonic detection at the brazed location of a brazing assembly according to Comparative Example 4.

Specific implementations of the disclosure are described in detail below. It is to be understood that the specific implementations described herein are merely used to describe and explain the disclosure and are not intended to limit the disclosure.

In a first aspect, the present disclosure provides an active metal brazing paste composition comprising a binder and a metal powder. Metal powders include active metal brazing powders and brazing-auxiliary metal powders. The brazing-auxiliary metal powder contains copper powder and/or copper-silver alloy powder. Active metal brazing powders are alloy powders containing Cu, Ag, and active metals. Based on the total weight of the metal powder, the active metal content is 1.5 wt% or more, the silver content is 40 wt% to 90 wt%, and the oxygen content is 0.5 wt% or less.

According to the above technical solution, the copper contained in the active metal brazing paste composition according to the present disclosure can be decomposed into oxygen at the brazing temperature, which promotes the consumption of carbon remaining after decomposition of the binder and carbon at the brazing interface. Prevents residues from affecting brazing quality. Additionally, conventional ternary alloy active metal brazing materials have a low content of active metals, and using conventional preparation methods, it is difficult to precisely control the content of active metals in ternary alloy products. In the brazing paste composition according to the present disclosure, the content of active metal brazing material in the total weight of the composition is adjusted and controlled by introducing an amount of copper powder or silver-copper alloy powder, which depends on the content of active metals in the ternary alloys. control requirements can be lowered and the difficulty of preparing ternary alloys can be reduced. By employing an active metal brazing paste composition according to the present disclosure, brazing quality can be stabilized and impacts on subsequent brazing processes are reduced. Meanwhile, copper powder and silver-copper alloy powder are inexpensive, which can reduce material costs after being added to the brazing paste.

In embodiments of the present disclosure, the oxygen content of the metal powder is less than 0.48, or less than 0.46 wt%, or less than 0.01 wt% to 0.5 wt%. In other embodiments of the disclosure, the oxygen content of the metal powder is 0.01 wt% to 0.48 wt%, or 0.01 wt% to 0.46 wt%, or 0.1 wt% to 0.5 wt%, or 0.1 wt% to 0.48 wt%, or 0.1 wt% to 0.46 wt%.

In an embodiment, the oxygen content of the brazing-assisting metal powder is 2 wt% or less, for example 0.3 wt% to 0.5 wt%, based on the total weight of the brazing-assisting metal powder, which reduces the reactivity of the copper in the brazing process. promotes and improves brazing quality. Additionally, the carbon content of the brazing-auxiliary metal powder is 0.75 wt% or less, for example 0.6 wt% or less, or 0.5 wt% or less. In other embodiments of the disclosure, the carbon content of the brazing-assisting metal powder is from 0.01 wt% to 0.75 wt%, or from 0.02 wt% to 0.6 wt%, or from 0.05 wt% to 0.5 wt%. In other embodiments of the disclosure, the carbon content of the brazing-auxiliary metal powder is 0.3 wt% or less, or 0.25 wt% or less, or 0.1 wt% or less, or 0.01 wt% to 0.3 wt%, or 0.01 wt% to 0.25 wt. %, or 0.01 wt% to 0.1 wt%, which prevents excess oxygen from being introduced into the brazing paste, which could affect the brazing performance of the active metals. The molar ratio of oxygen to carbon in the brazing-auxiliary metal powder is at least 2, for example between 2 and 8, between 2 and 6, or between 2.2 and 5.6.

In this implementation, the oxygen and carbon content in the brazing-auxiliary metal powder is appropriate, preventing the brazing performance of the brazing paste from being affected, thereby further improving the brazing quality.

In an embodiment, to further improve the brazing performance of the brazing paste composition, the content of the active metal is 1.8 wt% to 4.5 wt%, based on the total weight of the metal powder; The silver content is 42 wt% to 85 wt%; The oxygen content is 0.001 wt% to 0.3 wt%. In another embodiment of the present disclosure, based on the total weight of the metal powder, the content of active metal is 2 wt% to 4 wt%; The silver content is 45 wt% to 80 wt%; The oxygen content is 0.06 wt% to 0.2 wt%.

In the brazing paste composition according to the present disclosure, there are special restrictions on the weight ratio of brazing-auxiliary metal powder to active metal brazing powder, as long as it ensures that the contents of active metal, silver and oxygen in the brazing paste composition meet the above content range requirements. There is no For example, based on the total weight of the metal powder, the content of the brazing-auxiliary metal powder may be 10 wt% to 50 wt%, and the content of the active metal brazing powder may be 50 wt% to 90 wt%. . In another embodiment of the present disclosure, based on the total weight of the metal powder, the content of the brazing-auxiliary metal powder may be 15 wt% to 40 wt%, and the content of the active metal brazing powder may be 60 wt% to 85 wt. It may be %.

In the above embodiment, the content of active metal titanium in the brazing paste composition can be maintained within an appropriate range, thereby further improving the stability of the brazing quality of the active metal brazing paste composition.

In an embodiment, the active metal is selected from one or more of Ti, Zr, and Hf. In some implementations of the disclosure, the active metal is Ti, i.e., the active metal brazing powder is a copper-silver-titanium brazing powder; Based on the total weight of the active metal brazing powder, the content of the active metal is 1.5 wt% to 10 wt%. In another embodiment of the disclosure, the content of active metal is 2 wt% to 6 wt%, based on the total weight of the active metal brazing powder. The weight ratio of Ag to Cu in the active metal brazing powder is 3:7 to 9:1. In another implementation of the disclosure, the weight ratio of Ag to Cu in the active metal brazing powder is 6:4 to 8:2. In the above implementation, the brazing performance of the active metal brazing powder can be further improved, and the brazing quality can be further improved.

In embodiments, the oxygen content of the active metal brazing powder is 0.5 wt% or less, such as 0.01 wt% to 0.5 wt%, or 0.01 wt% to 0.45 wt%, or 0.02 wt% to 0.4 wt%.

In an embodiment, the particle size of the active metal brazing powder is 50 μm or less and the particle size of the brazing-auxiliary metal powder is 50 μm or less. In this implementation, the particle size of the active metal powder is highly consistent with the mesh number of the selected printing screen, thereby further improving the brazing quality.

In an embodiment, based on the total weight of the brazing paste composition, the content of metal powder is 80 wt% to 95 wt%; The binder content is 5 wt% to 20 wt%. In another embodiment of the present disclosure, based on the total weight of the brazing paste composition, the content of metal powder is 85 wt% to 90 wt%; The binder content is 10 wt% to 15 wt%. The binder may be a conventional brazing paste binder in the field, which is not specifically limited in the present disclosure.

In a second aspect, the present disclosure provides a brazing paste. The brazing paste is prepared by employing the active metal brazing paste composition according to the first aspect of the present disclosure.

In a third aspect, the disclosure provides a method for brazing ceramics and metals employing the active metal brazing paste composition according to the first aspect of the disclosure or the brazing paste according to the second aspect of the disclosure. . The method includes connecting the ceramics to be brazed and the metals to be brazed through a composition or brazing paste to form a connecting member to be brazed, and supplying the connecting member to be brazed into a vacuum brazing furnace to be heated and brazed, vacuum brazing. The content ratio of organic materials in the connecting member to be brazed to the effective volume of the furnace is not more than 0.4 g/m3.

In an embodiment, the method is such that the composition or brazing paste is printed onto the surface of the ceramics to be brazed, and baking is performed at 60°C to 100°C for 20 to 60 minutes - in another embodiment, the baking is performed at 70°C to 80°C for 30 minutes. Performed for minutes - ; The metals to be brazed are securely connected with the baked brazing paste to obtain a connecting member to be brazed; The connection member to be brazed is heated and supplied to a vacuum brazing furnace to be brazed, and the content ratio of organic materials in the connection member to be brazed to the effective volume of the vacuum brazing furnace is 0.3 g/m or less, and in another embodiment, The content ratio of organic materials in the connecting member to be brazed to the effective volume of the vacuum brazing furnace is 0.2 g/m 3 or less, whereby the organic materials are discharged quickly, thereby further improving the performance of the brazing paste during brazing.

In an embodiment, before the brazing process, the copper powder in the brazing-auxiliary metal powder is subjected to thermal oxidation treatment, in order to prevent the passivation layer of the copper powder from affecting the brazing quality; Depending on the method of thermal oxidation treatment, the copper powder is oxidized by heating in air or oxygen.

In the implementation, the brazing process is divided into five stages based on different temperature points, and the temperature points for the division are determined according to the melting point of the active metal powder in the brazing paste. The five stages include:

1. Temperature ramping stage from room temperature 25°C to a temperature range from 10°C to 100°C below the melting point of the active metal powder, for example from room temperature 25°C to a temperature range from 35°C to 65°C below the melting point of the active metal powder. temperature rise stage.

2. Heat preservation stage at the melting point of the active metal powder.

3. A temperature rise stage from the melting point of the active metal powder to the brazing temperature, where the brazing temperature is at least 50° C. higher than the equivalent melting point and at most 20° C. lower than the melting point of the member to be brazed.

4. Heat preservation stage at brazing temperature.

5. Subsequent cooling stage.

In implementations, methods employed in the brazing process include:

Vacuum pumping is performed after furnace charging, and heating is started after the vacuum degree is less than 0.1pa, entering the first stage. The heating rate in the first stage is less than 10°C/min before the temperature reaches 200°C. After the temperature exceeds 200℃, the temperature can be increased at a fixed rate or at different rates, or at a certain temperature, to ensure that the average heating rate is lower than 5℃/min and the maximum rate is lower than 10℃/min. Heat preservation can be performed. By controlling the heating rate with temperature rise and heat preservation methods, it is ensured that the maximum atmospheric pressure does not exceed 0.1pa and the temperature at the maximum atmospheric pressure does not exceed the maximum temperature in the first stage. The heat retention time of the second stage is 10 to 40 minutes. The average heating rate in the third stage is lower than 5° C./min, and the temperature rise duration does not exceed 90 minutes. The heat retention time in the fourth stage is 30 to 120 minutes. In the fifth stage, before the temperature reaches 600°C, the cooling rate is lower than 5°C/min. After the temperature reaches 600°C, the temperature is no longer controlled and natural cooling is performed.

The present disclosure is explained in more detail through examples below. The raw materials used in the examples may be obtained through commercial purchasing.

Example 1

The weight composition of the active metal brazing powder is 70 wt% Ag, 4 wt% Ti - particle size less than 50㎛ -, 0.08 wt% oxygen, and the remainder is copper.

The brazing-auxiliary metal powder is copper powder, the particle size of the copper powder is 50㎛ or less, the oxygen content is 0.2wt%, the carbon content is 0.05wt%, and the copper powder is subjected to thermal oxidation treatment, thereby reducing the oxygen content. Increase to 0.45 wt%.

The metal powder consists of 80 wt% of active metal brazing powder and 20 wt% of brazing-auxiliary metal powder, and a brazing paste is prepared by adding a binder. Based on the total weight of the brazing paste composition, the binder content is 15wt%. If the binder evaporates separately, 2.3 wt% of material remains at 400°C during heating. The binder used is 71.5 wt% terpilenol, 8 wt% stearic acid, 8 wt% polyethylene glycol 600, 4 wt% polyethylene glycol 2000, 2.5 wt% EC-90-110, 5 wt% oxalic acid, and 1 wt% polyurethane wax 6650. Contains ingredients.

The brazing paste is printed on silicon nitride ceramic and dried at 90°C for 30 minutes. Residual organic materials account for 0.9 wt% of the residual brazing paste. A copper plate is placed on the brazing paste, and after assembly, the brazing paste together with the copper plate is fed into a vacuum brazing furnace to be heated and brazed. The content ratio of residual organic materials on the brazing assembly charged in the furnace to the effective volume of the brazing furnace is 0.1 g/m3.

The brazing process is as follows: vacuum pumping is carried out after furnace charging, and after the vacuum degree is less than 0.1pa, heating is started and enters the first stage. The heating rate in the first stage is less than 5°C/min before the temperature reaches 200°C. After the temperature exceeds 200°C, the temperature is increased to 740°C at a fixed rate of 3°C/min. The maximum atmospheric pressure is 0.06pa, and the highest temperature at the maximum atmospheric pressure is 465℃. In the second stage, the heat retention time at 740° C. is 25 minutes. In the third stage, the temperature is increased to 890°C at 3°C/min. In the fourth stage, the heat preservation time at 890° C. is 45 minutes. In the fifth stage, cooling is carried out at 2°C/min to 600°C, and after the temperature reaches 600°C, the temperature is no longer controlled and natural cooling is carried out. An ultrasonic detection image of the brazed assembly at the brazed location is shown in Figure 1.

Example 2

The brazing process is the same as Example 1. The difference is that the weight composition of the active metal brazing powder is 70 wt% Ag, 3 wt% Ti, 0.08 wt% oxygen, and the balance Cu.

Example 3

The brazing process is the same as Example 1. The difference is that the brazing-auxiliary metal powder is a silver-copper alloy powder, the particle size of the silver-copper alloy powder is less than 50㎛, the silver content is 50wt%, the oxygen content is 0.2wt%, and the carbon content is 0.05 wt. %, and the remainder is Cu, and the silver-copper powder is subjected to thermal oxidation, thereby increasing the oxygen content to 0.45wt%.

Example 4

The brazing process is the same as Example 1. The difference is that the weight composition of the active metal brazing powder is 70 wt% Ag, 4 wt% Ti, 0.4 wt% oxygen, and the balance Cu.

Example 5

The brazing process is the same as Example 1. The difference is that the weight composition of the active metal brazing powder is 70 wt% Ag, 4 wt% Zr - particle size less than 50 μm, 0.08 wt% oxygen, and the balance Cu.

Comparative example One

The brazing process is the same as Example 1. The difference is that the metal powder contains only the active metal brazing powder and no brazing-auxiliary metal powder, and the brazing paste is prepared by adding a binder. An ultrasonic detection image of the brazed assembly at the brazed location is shown in Figure 2.

Comparative example 2

The brazing process is the same as Example 1. The difference is that the weight composition of the active metal brazing powder is 70 wt% Ag, 4 wt% Ti - particle size 50 μm or less - 0.8 wt% oxygen, and the balance Cu.

The brazing-auxiliary metal powder is copper powder, the particle size of the copper powder is 50 μm or less, the oxygen content is 3 wt%, and the carbon content is 1 wt%. An ultrasonic detection image of the brazed assembly at the brazed location is shown in Figure 3.

Comparative example 3

The brazing process is the same as Example 1. The difference is that the weight composition of the active metal brazing powder is 70 wt% Ag, 2 wt% Ti - particle size 50 μm or less - 0.8 wt% oxygen, and the balance Cu;

The metal powder consists of 30 wt% of active metal brazing powder and 70 wt% of brazing-auxiliary metal powder.

Comparative example 4

The brazing process is the same as Example 1. The difference is that the metal powder consists of 30 wt% of active metal brazing powder and 70 wt% of brazing-auxiliary metal powder, and the brazing paste is prepared by adding a binder. An ultrasonic detection image of the brazed assembly at the brazed location is shown in Figure 4.

Comparative example 5

The brazing process is the same as Example 1. The difference is that the content ratio of residual organic materials on the brazing assembly charged into the furnace to the effective volume of the brazing furnace is 0.8 g/m3.

test example

The peel strength test device is a general purpose testing machine. The test software is QCTech-A3, the peel speed is 50 mm/min, and the peel distance is >25 mm.

Table 1: Peel strength of brazing pastes for Examples 1 to 5 and Comparative Examples 1 to 5

According to analysis of the data in Table 1, comparing the data of Examples 1 to 5 and Comparative Examples 1 to 5, it is observed that copper powder is added to the metal powder in the brazing paste prepared in the present disclosure, This can reduce the amount of ternary alloy brazing powder used and lower the material cost of brazing paste. Additionally, compared to conventional brazing pastes containing only ternary alloy brazing powders, brazing pastes according to the present disclosure exhibit similar or better brazing quality and peel strength. Comparing the data of Example 1 and Example 4, in the present disclosure, it is observed that the brazing paste exhibits better brazing performance when the oxygen content in the metal powder is 0.06 wt% to 0.2 wt%; Comparing the data of Example 1 and Example 5, it is observed that the brazing performance of the brazing paste can be further improved when the content ratio of organic materials in the connecting member to be brazed to the effective volume of the vacuum brazing furnace is 0.4 g / ㎥ or less. .

Although the above examples show only a few implementations of the present disclosure and are described in specific detail, they should not be construed as limiting the patent scope of the present disclosure. It should be noted that those skilled in the art may also make various modifications and improvements without departing from the concept of the present disclosure, and such modifications and improvements fall within the protection scope of the present disclosure. Therefore, the scope of protection of the patent of this disclosure should follow the appended claims.

Claims (19)

An active metal brazing paste composition,
The composition includes a binder and a metal powder;
The metal powder includes active metal brazing powder and brazing-aid metal powder; The brazing-auxiliary metal powder includes copper powder and/or copper-silver alloy powder; The active metal brazing powder is an alloy powder containing copper, silver and active metal;
Based on the total weight of the metal powder, the content of the active metal is 1.5 wt% or more, the content of silver is 40 wt% to 90 wt%, and the content of oxygen is 0.5 wt% or less. The method of claim 1, wherein, based on the total weight of the brazing-auxiliary metal powder, the oxygen content of the brazing-auxiliary metal powder is 2 wt% or less, and the carbon content of the brazing-auxiliary metal powder is 0.75 wt% or less. and the molar ratio of oxygen to carbon in the brazing-auxiliary metal powder is 2 or more. The method of claim 1 or 2, wherein, based on the total weight of the brazing-auxiliary metal powder, the oxygen content of the brazing-auxiliary metal powder is 0.3 wt% to 0.5 wt%, and the brazing-auxiliary metal powder has an oxygen content of 0.3 wt% to 0.5 wt%. A brazing paste composition having a carbon content of 0.1 wt% or less. The method according to any one of claims 1 to 3, wherein, based on the total weight of the metal powder, the content of the brazing-auxiliary metal powder is 10 wt% to 50 wt%, and the content of the active metal brazing powder is A brazing paste composition comprising 50 wt% to 90 wt% silver. The method according to any one of claims 1 to 4, wherein, based on the total weight of the metal powder, the content of the active metal is 1.8 wt% to 4.5 wt%, and the content of silver is 42 wt% to 85 wt. %, and the oxygen content is 0.001 wt% to 0.3 wt%. The method of any one of claims 1 to 4, wherein, based on the total weight of the metal powder, the content of the active metal is 2 wt% to 4 wt%, and the content of silver is 45 wt% to 80 wt. %, and the oxygen content is 0.06 wt% to 0.2 wt%. The brazing paste composition according to any one of claims 1 to 6, wherein the active metal is selected from one or more of Ti, Zr and Hf. The brazing paste composition according to any one of claims 1 to 7, wherein the active metal is Ti. The brazing paste composition according to any one of claims 1 to 8, wherein the content of the active metal is 1.5 wt% to 10 wt%, based on the total weight of the active metal brazing powder. The brazing paste composition according to any one of claims 1 to 9, wherein the content of the active metal is 2 wt% to 6 wt%, based on the total weight of the active metal brazing powder. The brazing paste composition according to any one of claims 1 to 10, wherein the weight ratio of Ag to Cu in the active metal brazing powder is 3:7 to 9:1. The brazing paste composition according to any one of claims 1 to 11, wherein the weight ratio of Ag to Cu in the active metal brazing powder is 6:4 to 8:2. The brazing paste composition according to any one of claims 1 to 12, wherein the oxygen content of the active metal brazing powder is 0.5 wt% or less. The brazing paste composition according to any one of claims 1 to 13, wherein the particle size of the active metal brazing powder is 50 μm or less, and the particle size of the brazing-auxiliary metal powder is 50 μm or less. The method according to any one of claims 1 to 14, wherein, based on the total weight of the brazing paste composition, the content of the metal powder is 80 wt% to 95 wt%, and the content of the binder is 5 wt% to 5 wt%. 20 wt% brazing paste composition. The method of any one of claims 1 to 15, wherein, based on the total weight of the brazing paste composition, the content of the metal powder is 85 wt% to 90 wt%, and the content of the binder is 10 wt% to 10 wt%. 15 wt% brazing paste composition. As a brazing paste,
A brazing paste prepared by employing the active metal brazing paste composition according to any one of claims 1 to 16. A method for brazing ceramics and metals by employing an active metal brazing paste composition according to any one of claims 1 to 16 or a brazing paste according to claim 17, comprising:
Connecting the ceramics to be brazed and the metals to be brazed through the composition or the brazing paste to form a connecting member to be brazed, and supplying the connecting member to be brazed into a vacuum brazing furnace to be heated and brazed. A method comprising: a content ratio of organic materials of the connecting member to be brazed relative to the effective volume of the vacuum brazing furnace is 0.4 g/㎥ or less. According to clause 18,
Printing the composition or the brazing paste on the surfaces of the ceramics to be brazed and baking at 60°C to 100°C for 20 to 60 minutes;
securely connecting the metals to be brazed with baked brazing paste to obtain the connecting member to be brazed; and
Supplying the connecting member to be brazed to the vacuum brazing furnace to be heated and brazed.
The method further comprises, wherein the content ratio of organic materials of the connecting member to be brazed relative to the effective volume of the vacuum brazing furnace is 0.3 g/㎥ or less.